Fibrous nonwoven materials and fibrous nonwoven composite materials are widely used as products, or as components of products because they can be manufactured inexpensively and made to have specific characteristics. One approach to making fibrous nonwoven composite materials has been to join different types of nonwoven materials in a laminate.
The integrity of laminate materials described above depends in part on the techniques used to join the layers of the laminate. One disadvantage is that some effective bonding techniques add expense to the laminate materials and complexity to the manufacturing processes.
Fibrous nonwoven composites which contain a generally uniform distribution of component materials can have disadvantages which are related to the arrangement of the components. In particular, uniform distribution of certain fibers and particulates may promote linting and/or particle shedding. Another disadvantage is that composites which contain large proportions of uniformly distributed particulates or small fibers (e.g., pulp) generally have less integrity because less strength is provided by the fiber matirx. This phenomenon can be seen in poor abrasion resistance and tensile strength properties of generally homogeneous composites containing large proportions of adsorbents and/or particulates. This problem is particularly apparent when such a nonwoven composite is exposed to abrasion and/or tearing forces. However, since adsorbent sheets can be very useful, it is often highly desirable to incorporate large proportions of adsorbent materials in fibrous nonwoven composite structures.
Accordingly, there is a need for an adsorbent fibrous nonwoven composite structure which is inexpensive but has good abrasion resistance, integrity and strength characteristics. There is also a need for a fibrous nonwoven composite structure which has a relatively high adsorbent content and is inexpensive but has good abrasion resistance, integrity and linting or particle shedding characteristics.